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<a name="glib-Data-Checksums"></a><div class="titlepage"></div>
<div class="refnamediv"><table width="100%"><tr>
<td valign="top">
<h2><span class="refentrytitle"><a name="glib-Data-Checksums.top_of_page"></a>Data Checksums</span></h2>
<p>Data Checksums — computes the checksum for data</p>
</td>
<td class="gallery_image" valign="top" align="right"></td>
</tr></table></div>
<div class="refsect1">
<a name="glib-Data-Checksums.functions"></a><h2>Functions</h2>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="functions_return">
<col class="functions_name">
</colgroup>
<tbody>
<tr>
<td class="function_type">
<a class="link" href="glib-Basic-Types.html#gssize" title="gssize"><span class="returnvalue">gssize</span></a>
</td>
<td class="function_name">
<a class="link" href="glib-Data-Checksums.html#g-checksum-type-get-length" title="g_checksum_type_get_length ()">g_checksum_type_get_length</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="returnvalue">GChecksum</span></a> *
</td>
<td class="function_name">
<a class="link" href="glib-Data-Checksums.html#g-checksum-new" title="g_checksum_new ()">g_checksum_new</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="returnvalue">GChecksum</span></a> *
</td>
<td class="function_name">
<a class="link" href="glib-Data-Checksums.html#g-checksum-copy" title="g_checksum_copy ()">g_checksum_copy</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="glib-Data-Checksums.html#g-checksum-free" title="g_checksum_free ()">g_checksum_free</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="glib-Data-Checksums.html#g-checksum-reset" title="g_checksum_reset ()">g_checksum_reset</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="glib-Data-Checksums.html#g-checksum-update" title="g_checksum_update ()">g_checksum_update</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">const <a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="returnvalue">gchar</span></a> *
</td>
<td class="function_name">
<a class="link" href="glib-Data-Checksums.html#g-checksum-get-string" title="g_checksum_get_string ()">g_checksum_get_string</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="glib-Data-Checksums.html#g-checksum-get-digest" title="g_checksum_get_digest ()">g_checksum_get_digest</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="returnvalue">gchar</span></a> *
</td>
<td class="function_name">
<a class="link" href="glib-Data-Checksums.html#g-compute-checksum-for-data" title="g_compute_checksum_for_data ()">g_compute_checksum_for_data</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="returnvalue">gchar</span></a> *
</td>
<td class="function_name">
<a class="link" href="glib-Data-Checksums.html#g-compute-checksum-for-string" title="g_compute_checksum_for_string ()">g_compute_checksum_for_string</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="returnvalue">gchar</span></a> *
</td>
<td class="function_name">
<a class="link" href="glib-Data-Checksums.html#g-compute-checksum-for-bytes" title="g_compute_checksum_for_bytes ()">g_compute_checksum_for_bytes</a> <span class="c_punctuation">()</span>
</td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect1">
<a name="glib-Data-Checksums.other"></a><h2>Types and Values</h2>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="name">
<col class="description">
</colgroup>
<tbody>
<tr>
<td class="datatype_keyword">enum</td>
<td class="function_name"><a class="link" href="glib-Data-Checksums.html#GChecksumType" title="enum GChecksumType">GChecksumType</a></td>
</tr>
<tr>
<td class="datatype_keyword"> </td>
<td class="function_name"><a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum">GChecksum</a></td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect1">
<a name="glib-Data-Checksums.includes"></a><h2>Includes</h2>
<pre class="synopsis">#include &lt;glib.h&gt;
#include &lt;glib/gi18n.h&gt;
</pre>
</div>
<div class="refsect1">
<a name="glib-Data-Checksums.description"></a><h2>Description</h2>
<p>GLib provides a generic API for computing checksums (or "digests")
for a sequence of arbitrary bytes, using various hashing algorithms
like MD5, SHA-1 and SHA-256. Checksums are commonly used in various
environments and specifications.</p>
<p>GLib supports incremental checksums using the GChecksum data
structure, by calling <a class="link" href="glib-Data-Checksums.html#g-checksum-update" title="g_checksum_update ()"><code class="function">g_checksum_update()</code></a> as long as there's data
available and then using <a class="link" href="glib-Data-Checksums.html#g-checksum-get-string" title="g_checksum_get_string ()"><code class="function">g_checksum_get_string()</code></a> or
<a class="link" href="glib-Data-Checksums.html#g-checksum-get-digest" title="g_checksum_get_digest ()"><code class="function">g_checksum_get_digest()</code></a> to compute the checksum and return it either
as a string in hexadecimal form, or as a raw sequence of bytes. To
compute the checksum for binary blobs and NUL-terminated strings in
one go, use the convenience functions <a class="link" href="glib-Data-Checksums.html#g-compute-checksum-for-data" title="g_compute_checksum_for_data ()"><code class="function">g_compute_checksum_for_data()</code></a>
and <a class="link" href="glib-Data-Checksums.html#g-compute-checksum-for-string" title="g_compute_checksum_for_string ()"><code class="function">g_compute_checksum_for_string()</code></a>, respectively.</p>
<p>Support for checksums has been added in GLib 2.16</p>
</div>
<div class="refsect1">
<a name="glib-Data-Checksums.functions_details"></a><h2>Functions</h2>
<div class="refsect2">
<a name="g-checksum-type-get-length"></a><h3>g_checksum_type_get_length ()</h3>
<pre class="programlisting"><a class="link" href="glib-Basic-Types.html#gssize" title="gssize"><span class="returnvalue">gssize</span></a>
g_checksum_type_get_length (<em class="parameter"><code><a class="link" href="glib-Data-Checksums.html#GChecksumType" title="enum GChecksumType"><span class="type">GChecksumType</span></a> checksum_type</code></em>);</pre>
<p>Gets the length in bytes of digests of type <em class="parameter"><code>checksum_type</code></em>
</p>
<div class="refsect3">
<a name="g-checksum-type-get-length.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>checksum_type</p></td>
<td class="parameter_description"><p>a <a class="link" href="glib-Data-Checksums.html#GChecksumType" title="enum GChecksumType"><span class="type">GChecksumType</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="g-checksum-type-get-length.returns"></a><h4>Returns</h4>
<p> the checksum length, or -1 if <em class="parameter"><code>checksum_type</code></em>
is
not supported.</p>
</div>
<p class="since">Since: <a class="link" href="api-index-2-16.html#api-index-2.16">2.16</a></p>
</div>
<hr>
<div class="refsect2">
<a name="g-checksum-new"></a><h3>g_checksum_new ()</h3>
<pre class="programlisting"><a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="returnvalue">GChecksum</span></a> *
g_checksum_new (<em class="parameter"><code><a class="link" href="glib-Data-Checksums.html#GChecksumType" title="enum GChecksumType"><span class="type">GChecksumType</span></a> checksum_type</code></em>);</pre>
<p>Creates a new <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a>, using the checksum algorithm <em class="parameter"><code>checksum_type</code></em>
.
If the <em class="parameter"><code>checksum_type</code></em>
 is not known, <a class="link" href="glib-Standard-Macros.html#NULL:CAPS" title="NULL"><code class="literal">NULL</code></a> is returned.
A <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a> can be used to compute the checksum, or digest, of an
arbitrary binary blob, using different hashing algorithms.</p>
<p>A <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a> works by feeding a binary blob through <a class="link" href="glib-Data-Checksums.html#g-checksum-update" title="g_checksum_update ()"><code class="function">g_checksum_update()</code></a>
until there is data to be checked; the digest can then be extracted
using <a class="link" href="glib-Data-Checksums.html#g-checksum-get-string" title="g_checksum_get_string ()"><code class="function">g_checksum_get_string()</code></a>, which will return the checksum as a
hexadecimal string; or <a class="link" href="glib-Data-Checksums.html#g-checksum-get-digest" title="g_checksum_get_digest ()"><code class="function">g_checksum_get_digest()</code></a>, which will return a
vector of raw bytes. Once either <a class="link" href="glib-Data-Checksums.html#g-checksum-get-string" title="g_checksum_get_string ()"><code class="function">g_checksum_get_string()</code></a> or
<a class="link" href="glib-Data-Checksums.html#g-checksum-get-digest" title="g_checksum_get_digest ()"><code class="function">g_checksum_get_digest()</code></a> have been called on a <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a>, the checksum
will be closed and it won't be possible to call <a class="link" href="glib-Data-Checksums.html#g-checksum-update" title="g_checksum_update ()"><code class="function">g_checksum_update()</code></a>
on it anymore.</p>
<div class="refsect3">
<a name="g-checksum-new.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>checksum_type</p></td>
<td class="parameter_description"><p>the desired type of checksum</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="g-checksum-new.returns"></a><h4>Returns</h4>
<p>the newly created <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a>, or <a class="link" href="glib-Standard-Macros.html#NULL:CAPS" title="NULL"><code class="literal">NULL</code></a>.
Use <a class="link" href="glib-Data-Checksums.html#g-checksum-free" title="g_checksum_free ()"><code class="function">g_checksum_free()</code></a> to free the memory allocated by it. </p>
<p><span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span></p>
</div>
<p class="since">Since: <a class="link" href="api-index-2-16.html#api-index-2.16">2.16</a></p>
</div>
<hr>
<div class="refsect2">
<a name="g-checksum-copy"></a><h3>g_checksum_copy ()</h3>
<pre class="programlisting"><a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="returnvalue">GChecksum</span></a> *
g_checksum_copy (<em class="parameter"><code>const <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a> *checksum</code></em>);</pre>
<p>Copies a <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a>. If <em class="parameter"><code>checksum</code></em>
 has been closed, by calling
<a class="link" href="glib-Data-Checksums.html#g-checksum-get-string" title="g_checksum_get_string ()"><code class="function">g_checksum_get_string()</code></a> or <a class="link" href="glib-Data-Checksums.html#g-checksum-get-digest" title="g_checksum_get_digest ()"><code class="function">g_checksum_get_digest()</code></a>, the copied
checksum will be closed as well.</p>
<div class="refsect3">
<a name="g-checksum-copy.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>checksum</p></td>
<td class="parameter_description"><p>the <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a> to copy</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="g-checksum-copy.returns"></a><h4>Returns</h4>
<p> the copy of the passed <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a>. Use <a class="link" href="glib-Data-Checksums.html#g-checksum-free" title="g_checksum_free ()"><code class="function">g_checksum_free()</code></a>
when finished using it.</p>
</div>
<p class="since">Since: <a class="link" href="api-index-2-16.html#api-index-2.16">2.16</a></p>
</div>
<hr>
<div class="refsect2">
<a name="g-checksum-free"></a><h3>g_checksum_free ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
g_checksum_free (<em class="parameter"><code><a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a> *checksum</code></em>);</pre>
<p>Frees the memory allocated for <em class="parameter"><code>checksum</code></em>
.</p>
<div class="refsect3">
<a name="g-checksum-free.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>checksum</p></td>
<td class="parameter_description"><p>a <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<p class="since">Since: <a class="link" href="api-index-2-16.html#api-index-2.16">2.16</a></p>
</div>
<hr>
<div class="refsect2">
<a name="g-checksum-reset"></a><h3>g_checksum_reset ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
g_checksum_reset (<em class="parameter"><code><a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a> *checksum</code></em>);</pre>
<p>Resets the state of the <em class="parameter"><code>checksum</code></em>
 back to its initial state.</p>
<div class="refsect3">
<a name="g-checksum-reset.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>checksum</p></td>
<td class="parameter_description"><p>the <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a> to reset</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<p class="since">Since: <a class="link" href="api-index-2-18.html#api-index-2.18">2.18</a></p>
</div>
<hr>
<div class="refsect2">
<a name="g-checksum-update"></a><h3>g_checksum_update ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
g_checksum_update (<em class="parameter"><code><a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a> *checksum</code></em>,
                   <em class="parameter"><code>const <a class="link" href="glib-Basic-Types.html#guchar" title="guchar"><span class="type">guchar</span></a> *data</code></em>,
                   <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gssize" title="gssize"><span class="type">gssize</span></a> length</code></em>);</pre>
<p>Feeds <em class="parameter"><code>data</code></em>
 into an existing <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a>. The checksum must still be
open, that is <a class="link" href="glib-Data-Checksums.html#g-checksum-get-string" title="g_checksum_get_string ()"><code class="function">g_checksum_get_string()</code></a> or <a class="link" href="glib-Data-Checksums.html#g-checksum-get-digest" title="g_checksum_get_digest ()"><code class="function">g_checksum_get_digest()</code></a> must
not have been called on <em class="parameter"><code>checksum</code></em>
.</p>
<div class="refsect3">
<a name="g-checksum-update.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>checksum</p></td>
<td class="parameter_description"><p>a <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>data</p></td>
<td class="parameter_description"><p>buffer used to compute the checksum. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="Parameter points to an array of items."><span class="acronym">array</span></acronym> length=length][<acronym title="Generics and defining elements of containers and arrays."><span class="acronym">element-type</span></acronym> guint8]</span></td>
</tr>
<tr>
<td class="parameter_name"><p>length</p></td>
<td class="parameter_description"><p>size of the buffer, or -1 if it is a null-terminated string.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: <a class="link" href="api-index-2-16.html#api-index-2.16">2.16</a></p>
</div>
<hr>
<div class="refsect2">
<a name="g-checksum-get-string"></a><h3>g_checksum_get_string ()</h3>
<pre class="programlisting">const <a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="returnvalue">gchar</span></a> *
g_checksum_get_string (<em class="parameter"><code><a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a> *checksum</code></em>);</pre>
<p>Gets the digest as an hexadecimal string.</p>
<p>Once this function has been called the <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a> can no longer be
updated with <a class="link" href="glib-Data-Checksums.html#g-checksum-update" title="g_checksum_update ()"><code class="function">g_checksum_update()</code></a>.</p>
<p>The hexadecimal characters will be lower case.</p>
<div class="refsect3">
<a name="g-checksum-get-string.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>checksum</p></td>
<td class="parameter_description"><p>a <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="g-checksum-get-string.returns"></a><h4>Returns</h4>
<p> the hexadecimal representation of the checksum. The
returned string is owned by the checksum and should not be modified
or freed.</p>
</div>
<p class="since">Since: <a class="link" href="api-index-2-16.html#api-index-2.16">2.16</a></p>
</div>
<hr>
<div class="refsect2">
<a name="g-checksum-get-digest"></a><h3>g_checksum_get_digest ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
g_checksum_get_digest (<em class="parameter"><code><a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a> *checksum</code></em>,
                       <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#guint8" title="guint8"><span class="type">guint8</span></a> *buffer</code></em>,
                       <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gsize" title="gsize"><span class="type">gsize</span></a> *digest_len</code></em>);</pre>
<p>Gets the digest from <em class="parameter"><code>checksum</code></em>
 as a raw binary vector and places it
into <em class="parameter"><code>buffer</code></em>
. The size of the digest depends on the type of checksum.</p>
<p>Once this function has been called, the <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a> is closed and can
no longer be updated with <a class="link" href="glib-Data-Checksums.html#g-checksum-update" title="g_checksum_update ()"><code class="function">g_checksum_update()</code></a>.</p>
<p><span class="annotation">[<acronym title="Exposed in C code, not necessarily available in other languages."><span class="acronym">skip</span></acronym>]</span></p>
<div class="refsect3">
<a name="g-checksum-get-digest.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>checksum</p></td>
<td class="parameter_description"><p>a <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>buffer</p></td>
<td class="parameter_description"><p>output buffer</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>digest_len</p></td>
<td class="parameter_description"><p>an inout parameter. The caller initializes it to the size of <em class="parameter"><code>buffer</code></em>
.
After the call it contains the length of the digest.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: <a class="link" href="api-index-2-16.html#api-index-2.16">2.16</a></p>
</div>
<hr>
<div class="refsect2">
<a name="g-compute-checksum-for-data"></a><h3>g_compute_checksum_for_data ()</h3>
<pre class="programlisting"><a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="returnvalue">gchar</span></a> *
g_compute_checksum_for_data (<em class="parameter"><code><a class="link" href="glib-Data-Checksums.html#GChecksumType" title="enum GChecksumType"><span class="type">GChecksumType</span></a> checksum_type</code></em>,
                             <em class="parameter"><code>const <a class="link" href="glib-Basic-Types.html#guchar" title="guchar"><span class="type">guchar</span></a> *data</code></em>,
                             <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gsize" title="gsize"><span class="type">gsize</span></a> length</code></em>);</pre>
<p>Computes the checksum for a binary <em class="parameter"><code>data</code></em>
 of <em class="parameter"><code>length</code></em>
. This is a
convenience wrapper for <a class="link" href="glib-Data-Checksums.html#g-checksum-new" title="g_checksum_new ()"><code class="function">g_checksum_new()</code></a>, <a class="link" href="glib-Data-Checksums.html#g-checksum-get-string" title="g_checksum_get_string ()"><code class="function">g_checksum_get_string()</code></a>
and <a class="link" href="glib-Data-Checksums.html#g-checksum-free" title="g_checksum_free ()"><code class="function">g_checksum_free()</code></a>.</p>
<p>The hexadecimal string returned will be in lower case.</p>
<div class="refsect3">
<a name="g-compute-checksum-for-data.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>checksum_type</p></td>
<td class="parameter_description"><p>a <a class="link" href="glib-Data-Checksums.html#GChecksumType" title="enum GChecksumType"><span class="type">GChecksumType</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>data</p></td>
<td class="parameter_description"><p>binary blob to compute the digest of. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="Parameter points to an array of items."><span class="acronym">array</span></acronym> length=length][<acronym title="Generics and defining elements of containers and arrays."><span class="acronym">element-type</span></acronym> guint8]</span></td>
</tr>
<tr>
<td class="parameter_name"><p>length</p></td>
<td class="parameter_description"><p>length of <em class="parameter"><code>data</code></em>
</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="g-compute-checksum-for-data.returns"></a><h4>Returns</h4>
<p> the digest of the binary data as a string in hexadecimal.
The returned string should be freed with <a class="link" href="glib-Memory-Allocation.html#g-free" title="g_free ()"><code class="function">g_free()</code></a> when done using it.</p>
</div>
<p class="since">Since: <a class="link" href="api-index-2-16.html#api-index-2.16">2.16</a></p>
</div>
<hr>
<div class="refsect2">
<a name="g-compute-checksum-for-string"></a><h3>g_compute_checksum_for_string ()</h3>
<pre class="programlisting"><a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="returnvalue">gchar</span></a> *
g_compute_checksum_for_string (<em class="parameter"><code><a class="link" href="glib-Data-Checksums.html#GChecksumType" title="enum GChecksumType"><span class="type">GChecksumType</span></a> checksum_type</code></em>,
                               <em class="parameter"><code>const <a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="type">gchar</span></a> *str</code></em>,
                               <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gssize" title="gssize"><span class="type">gssize</span></a> length</code></em>);</pre>
<p>Computes the checksum of a string.</p>
<p>The hexadecimal string returned will be in lower case.</p>
<div class="refsect3">
<a name="g-compute-checksum-for-string.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>checksum_type</p></td>
<td class="parameter_description"><p>a <a class="link" href="glib-Data-Checksums.html#GChecksumType" title="enum GChecksumType"><span class="type">GChecksumType</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>str</p></td>
<td class="parameter_description"><p>the string to compute the checksum of</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>length</p></td>
<td class="parameter_description"><p>the length of the string, or -1 if the string is null-terminated.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="g-compute-checksum-for-string.returns"></a><h4>Returns</h4>
<p> the checksum as a hexadecimal string. The returned string
should be freed with <a class="link" href="glib-Memory-Allocation.html#g-free" title="g_free ()"><code class="function">g_free()</code></a> when done using it.</p>
</div>
<p class="since">Since: <a class="link" href="api-index-2-16.html#api-index-2.16">2.16</a></p>
</div>
<hr>
<div class="refsect2">
<a name="g-compute-checksum-for-bytes"></a><h3>g_compute_checksum_for_bytes ()</h3>
<pre class="programlisting"><a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="returnvalue">gchar</span></a> *
g_compute_checksum_for_bytes (<em class="parameter"><code><a class="link" href="glib-Data-Checksums.html#GChecksumType" title="enum GChecksumType"><span class="type">GChecksumType</span></a> checksum_type</code></em>,
                              <em class="parameter"><code><a class="link" href="glib-Byte-Arrays.html#GBytes" title="GBytes"><span class="type">GBytes</span></a> *data</code></em>);</pre>
<p>Computes the checksum for a binary <em class="parameter"><code>data</code></em>
. This is a
convenience wrapper for <a class="link" href="glib-Data-Checksums.html#g-checksum-new" title="g_checksum_new ()"><code class="function">g_checksum_new()</code></a>, <a class="link" href="glib-Data-Checksums.html#g-checksum-get-string" title="g_checksum_get_string ()"><code class="function">g_checksum_get_string()</code></a>
and <a class="link" href="glib-Data-Checksums.html#g-checksum-free" title="g_checksum_free ()"><code class="function">g_checksum_free()</code></a>.</p>
<p>The hexadecimal string returned will be in lower case.</p>
<div class="refsect3">
<a name="g-compute-checksum-for-bytes.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>checksum_type</p></td>
<td class="parameter_description"><p>a <a class="link" href="glib-Data-Checksums.html#GChecksumType" title="enum GChecksumType"><span class="type">GChecksumType</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>data</p></td>
<td class="parameter_description"><p>binary blob to compute the digest of</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="g-compute-checksum-for-bytes.returns"></a><h4>Returns</h4>
<p> the digest of the binary data as a string in hexadecimal.
The returned string should be freed with <a class="link" href="glib-Memory-Allocation.html#g-free" title="g_free ()"><code class="function">g_free()</code></a> when done using it.</p>
</div>
<p class="since">Since: <a class="link" href="api-index-2-34.html#api-index-2.34">2.34</a></p>
</div>
</div>
<div class="refsect1">
<a name="glib-Data-Checksums.other_details"></a><h2>Types and Values</h2>
<div class="refsect2">
<a name="GChecksumType"></a><h3>enum GChecksumType</h3>
<p>The hashing algorithm to be used by <a class="link" href="glib-Data-Checksums.html#GChecksum" title="GChecksum"><span class="type">GChecksum</span></a> when performing the
digest of some data.</p>
<p>Note that the <a class="link" href="glib-Data-Checksums.html#GChecksumType" title="enum GChecksumType"><span class="type">GChecksumType</span></a> enumeration may be extended at a later
date to include new hashing algorithm types.</p>
<div class="refsect3">
<a name="GChecksumType.members"></a><h4>Members</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="300px" class="enum_members_name">
<col class="enum_members_description">
<col width="200px" class="enum_members_annotations">
</colgroup>
<tbody>
<tr>
<td class="enum_member_name"><p><a name="G-CHECKSUM-MD5:CAPS"></a>G_CHECKSUM_MD5</p></td>
<td class="enum_member_description">
<p>Use the MD5 hashing algorithm</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
<tr>
<td class="enum_member_name"><p><a name="G-CHECKSUM-SHA1:CAPS"></a>G_CHECKSUM_SHA1</p></td>
<td class="enum_member_description">
<p>Use the SHA-1 hashing algorithm</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
<tr>
<td class="enum_member_name"><p><a name="G-CHECKSUM-SHA256:CAPS"></a>G_CHECKSUM_SHA256</p></td>
<td class="enum_member_description">
<p>Use the SHA-256 hashing algorithm</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
<tr>
<td class="enum_member_name"><p><a name="G-CHECKSUM-SHA512:CAPS"></a>G_CHECKSUM_SHA512</p></td>
<td class="enum_member_description">
<p>Use the SHA-512 hashing algorithm (Since: 2.36)</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
<tr>
<td class="enum_member_name"><p><a name="G-CHECKSUM-SHA384:CAPS"></a>G_CHECKSUM_SHA384</p></td>
<td class="enum_member_description">
<p>Use the SHA-384 hashing algorithm (Since: 2.51)</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: <a class="link" href="api-index-2-16.html#api-index-2.16">2.16</a></p>
</div>
<hr>
<div class="refsect2">
<a name="GChecksum"></a><h3>GChecksum</h3>
<pre class="programlisting">typedef struct _GChecksum GChecksum;</pre>
<p>An opaque structure representing a checksumming operation.
To create a new GChecksum, use <a class="link" href="glib-Data-Checksums.html#g-checksum-new" title="g_checksum_new ()"><code class="function">g_checksum_new()</code></a>. To free
a GChecksum, use <a class="link" href="glib-Data-Checksums.html#g-checksum-free" title="g_checksum_free ()"><code class="function">g_checksum_free()</code></a>.</p>
<p class="since">Since: <a class="link" href="api-index-2-16.html#api-index-2.16">2.16</a></p>
</div>
</div>
</div>
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